A wide variety of portable electronic devices nowadays is provided with components for capturing image data. Examples for such electronic devices include portable communication devices which may include a camera. For illustration, modern mobile telephones or personal digital assistants may be equipped with a camera. With increasing performance of the image capturing components of such devices, it becomes increasingly desirable to perform additional image processing on the captured images.
Owing to the computational complexity of some image processing functions, one approach to address the above need of providing additional image processing features is to interface the portable electronic equipment with a computer. The computer may execute dedicated software for processing images captured by the portable electronic equipment. Because captured images must first be transferred to the computer for further processing, this approach may be inconvenient for a user.
Another approach is to implement additional image processing functions in the portable electronic device. For illustration, functions for forming composite images may be provided in the portable electronic device. Such functions may include steps such as computing a difference image of a first image having an object of interest positioned in front of a background and of a second image only showing the background, to thereby identify the outline of the object of interest. While such operations require only basic image processing functions, such as computing difference images, the dedicated user which are required to determine the object outline may be inconvenient. Also, techniques which require a background to remain essentially the same while successive exposures are being recorded may be of limited value to a wide variety of scenarios where the background is not stationary, as is the case when at least part of the background shows moving objects.